In the field of plastic surgery, non-invasive procedures have enjoyed increasing popularity over the past ten years. The most common procedures include injection of liquid fillers in facial lines and wrinkles as well as the use of agents which paralyze selective muscles of the face in order to provide diminishment and smoothing of wrinkles. Typically, a dermal filler or paralytic agent such as Botox® Cosmetic (onabotulinumtoxinA), is used on a recurrent outpatient basis. Such agents typically are available in sterile vials of product in freeze-dried form. The clinician will reconstitute the preparation according to a specific recipe of sterile saline (fluid) added to the vial of product. Once mixed, the preparation is drawn up into a syringe, for subdermal delivery using a small bore medical needle. The most common delivery method uses a one cc disposable syringe which is fitted with a disposable needle. Importantly, small, reproducible allotments of the fluid are delivered via multiple injections into the muscles of the face, such as the frontalis muscle in a field of the face which would benefit from treatment.
Further, it is well known that the use of a small syringe during injections of the face on a subject who is sitting in a chair is generally uncomfortable for the health care provider and subject to unsteady maneuvering of the syringe due to the necessity of pushing on the plunger which is located at the rear end of the syringe assembly, while trying to hold the syringe steady. Accordingly, there remains a need to provide a handheld dispenser or syringe that can be more stable or desired tiller or fluid amounts from a handheld dispenser or syringe in such applications in order to provide predictable and/or desired results.